Equivariance beyond lower-level visual areas remains unestablished

Establish whether the orientation column structure and spatiotemporal receptive fields in cortex confer equivariance to small visual transformations across the entire visual hierarchy, rather than being limited to lower-level visual areas.

Background

The authors review proposals that orientation columns and spatiotemporal receptive fields may support equivariance to small visual transformations in early visual cortex.

They explicitly note that it has not been shown whether this property extends throughout higher stages of the visual hierarchy and argue that their spacetime perspective suggests such an extension should hold.